Surfactants sulfosuccinates

In the manufacture of coating materials, paints, varnishes, lacquers, dyestuff pigments, binding materials, and binders, surfactants are of great importance. Most of the systems used in these fields are dispersed. Therefore surfactants can accelerate the preparations of dispersions and improve their stability. For rewetting processes, like the so-called flush process, besides other anionic surfactants sulfosuccinates are also used. 

Results can sometimes be unexpected. The first study of this type made use of labeled Aerosol OTN [111], an anionic surfactant, also known as di-n-octylsodium sulfosuccinate. The measured F was twice that in Eq. III-93 and it was realized that hydrolysis had occurred, that is, X + H2O = HX + OH , and that it was the undissociated acid HX that was surface-active. Since pH was essentially constant, the activity of HX was just proportional to C. A similar behavior was found for aqueous sodium stearate [112]. 

A.lkyl Sulfosuccinate Half Asters. These detergents are prepared by reaction of maleic anhydride and a primary fatty alcohol, followed by sulfonation with sodium bisulfite. A typical member of this group is disodium lauryl sulfosucciaate [26838-05-1]. Although not known as effective foamers, these surfactants can boost foams and act as stabilizers when used ia combination with other anionic surfactants. In combination with alkyl sulfates, they are said to reduce the irritation effects of the latter (6). 

Baby Shampoos. These shampoos, specifically marketed for small children, feature a non-eye stinging quaHty. The majority of the products in this category are based on an amphoteric detergent system a system combining the use of an imidazoline amphoteric with an ethoxylated nonionic surfactant has been successfiiUy marketed (15,16). The sulfosuccinates also have been suggested for baby shampoo preparation because of thek mildness... 

Specialty sulfonic acid-based surfactants make up a rather large portion of surfactant production in the United States. Approximately 136,000 metric tons of specialty sulfonic acid-based surfactants were produced in 1992, which included alpha-olefin sulfonates, sulfobetaines, sulfosuccinates, and alkyl diphenyl ether disulfonates (64). These materials found use in the areas of household cleaning products, cosmetics (qv), toiletries, emulsion polymerization, and agricultural chemical manufacture. 

LialkylSulfosuccinates. Introduced in 1939 by the American Cyanamid Company under the Aerosol trademark, dialkyl sulfosuccinates have become widely used specialty surfactants (Table 8) (9). Within the limitations in hydrolytic stabiUty imposed by the presence of the ester groups, sulfosuccinates are mild, versatile surfactants used when strong wetting, detergency, rewetting, penetration, and solubilization effectiveness is needed. 

Chemical Designations - Synonyms Aerosol Surfactant Alrowet D65 Bis(2-ethylhexyl)sodlum Sulfosuccinate Di(2-ethylhexyl)Sulfosuccinate, Sodium Salt Sodium Dioctyl Sulfosuccinate Chemical Formula C8H,700CCH2CH-(S03Na)C00C8H,7. 

For the manufacturing of sulfosuccinic acid esters, which belong to a special class of surfactants, maleic acid anhydride is needed. Maleic acid anhydride is an important intermediate chemical of the chemical industry. Its worldwide output amounts to about 800,000 tons (1990) [64]. Maleic acid is produced by catalytic vapor phase oxidation process of benzene or n-C4 hydrocarbons in fixed bed or fluidized bed reactors according the following reaction equations. The heat of reaction of the exothermic oxidation processes is very high. 

LDL compositions containing AOS, a sulfosuccinic acid ester, a zwitterionic and a nonionic surfactant have been described by Noguera et al. [76]. Such compositions have good cleaning and foaming power and are useful too for shampoo and laundry-cleaning purposes. 

A central task for modern surfactant types in household and cosmetic use is good applicational behavior—foaming, wetting properties, hardness sensitivity, and so on—combined with reasonable dermatological properties. This chapter will give an overview about one of these the sulfosuccinates (Fig. 1). 

These anionic surfactants are based on the petrochemically gained maleic acid anhydride. Sulfosuccinates are surface-active metal (mostly sodium) salts of either monoester or diesters of sulfosuccinic acid. 

More recent publications on sulfosuccinates have confirmed the minimal or close to zero skin and eye irritation caused by these products. In a general screening of product safety evaluation methods the authors [16] rejected the sulfosuccinate from further consideration in the statistical analysis of experimental data (variance analysis) because the product had not shown any irritation in the Duhring-Chamber test. The sulfosuccinate (based on fatty alcohol ethoxy late) was tested in a screening with 14 other surfactants, namely, alkyl sulfates, sulfonates, ether sulfates, and a protein fatty acid condensation product. 

A favorable review of sulfosuccinate containing formulations is given in Ref. 17. The review was prompted by the U.S. Food and Drug Administration (FDA) when certain formulations based on other common surfactants gave rise to irritation of the urinary test. 

Analytical methods for qualitative and quantitative determination of all kinds of surfactants have long been established. There can be found either wet chemical methods—like titration—or methods of instrumental analytics. A classical method for anionic surfactants is the so-called two-phase-titration [63]. Using this method nearly every molecule bearing an anionic group is detected. The correct determination of sulfosuccinates is limited to the interferences of the other ingredients and byproducts present. With few exceptions all sulfosuccinates react with special indicators, e.g., hyamin 1622 (Rohm and Haas), to form an anionic-cationic complex and hence are to be analyzed by active content titration. 

The storage behavior of sulfosuccinates is generally enormously improved by the addition of anionic surfactants. It is well known that addition of only 10% of NLES, for example, doubles the possible storage time of a sensitive ... 

The broad spectrum of the raw goods occurring in the leather and fur industry [95] necessitates various wet treatment processes in which surfactants and emulsifiers play a big role, e.g., in the regeneration of raw goods, which are preserved with salt, or by drying short-chain sulfosuccinates. To achieve hydro-phobizing effects, sulfosuccinate as emulsifiers are fixed on the surface by salts of aluminum or chromium. 

Sulfosuccinates have a history of safety as their use in consumers products in the past years has proven. However, few toxicity data can be found in the literature, mostly in connection with the evaluation of other surfactants. As the figures show, all sulfosuccinates and sulfosuccinamates described in this chapter have an acute oral toxicity (LD50) of >2000 mg/kg. Results are listed in Table 20. 

DOSS, because of its use in foods and pharmaceuticals, was the target of numerous studies concerning toxicity, bioaccumulation, and reproduction as well as gastroenterological issues, so it can be concluded that DOSS is one of the best examined surfactants in the sulfosuccinates. 

Comparative primary skin irritation scores of surfactant solutions (15% active content) show various types of sulfosuccinates as being the least irritant materials, well below sodium laureth-3 sulfate. It was also shown that an increase in degree of ethoxylation reduces skin and eye irritation, leading to laureth-3 (lauryl alcohol with 3 mol ethylene oxide) as the ideal organic raw material [17]. The results are given in Fig. 9 for eye irritation and in Fig. 10 for skin irritation. 

In a broad evaluation also the sulfosuccinate disodium laureth sulfosuccinate (DLSS) was a part of a variety of surfactants tested for their dermatological mildness, and some different test methods were applied [16]. Products were compared applying in vitro methods (Zein test, hemolysis) and in vivo methods (Duhring-Chamber test, skin mildness by intracutaneous test on mice and topical application on hairless mice, mucous membrane irritation according to the Draize procedure on rabbit eyes). In the Duhring-Chamber test the DLSS elicited no reactions in the animal tests it ranged in the least irritant third of the 15 products tested. 

In Fig. 11 results are given for sulfosuccinate surfactants of different molecular structure tested according to the Draize skin irritation procedure. The test method defines test scores verbally as described in Table 21. The data in Fig. 11 prove the nonirritant character of sulfosuccinates tested at 10% concentration. Similar results were found for another group of sulfosuccinates [103]... 

Water serves as a base value in this test and sodium lauryl sulfate as a well-known irritating surfactant. Lauryl ether sulfate served as a substance with high sales volume and good skin tolerance. As was to be expected, lauryl ether sulfate scored only slightly better than lauryl sulfate. Sulfosuccinate values obtained were classified under little skin roughening effect. ... 

In two studies the cleansing and irritancy behavior of surfactants [106,107] were examined. An automated skin brushing method using a specific test soil and an epicutaneous irritation test on the dorsum of volunteers were applied. A sodium sulfosuccinate monoester based on a fatty alcohol ethoxylate gave very favorable results with respect to skin mildness although this concurred with low detergency. 

Sulfosuccinates are not only less irritating to skin and mucus membranes than other surfactants, but it was also found that they reduce skin irritation of other surfactants used in skin and hair care products. In particular, the effect on sodium lauryl ether sulfate was found to be most pronounced [103]. Figure 14 shows the mollifying effect of disodium oleic acid monoethanol amide sulfo-succinate when blended with anionic surfactant at a total concentration of 15%. 

Good confirmation of these figures is given in Ref. 111. In this evaluation, a sulfosuccinate was run both in the Zein test and in the RBC test. With both results the sulfosuccinate is described as the second best compatible surfactant after a high molecular weight protein fatty acid condensate. 

Dispersant compositions for the treatment of oil spills at the surface of the water consist of a mixture of water, a hydrocarbon solvent, and a mixture of surfactants consisting of 55% to 65% by weight of emulsifiers and 35% to 45% by weight of dioctyl sodium sulfosuccinate. The emulsifying agents consist of a mixture of various sorbitan oleates [351-354]. 

Surfactants employed for w/o-ME formation, listed in Table 1, are more lipophilic than those employed in aqueous systems, e.g., for micelles or oil-in-water emulsions, having a hydrophilic-lipophilic balance (HLB) value of around 8-11 [4-40]. The most commonly employed surfactant for w/o-ME formation is Aerosol-OT, or AOT [sodium bis(2-ethylhexyl) sulfosuccinate], containing an anionic sulfonate headgroup and two hydrocarbon tails. Common cationic surfactants, such as cetyl trimethyl ammonium bromide (CTAB) and trioctylmethyl ammonium bromide (TOMAC), have also fulfilled this purpose however, cosurfactants (e.g., fatty alcohols, such as 1-butanol or 1-octanol) must be added for a monophasic w/o-ME (Winsor IV) system to occur. Nonionic and mixed ionic-nonionic surfactant systems have received a great deal of attention recently because they are more biocompatible and they promote less inactivation of biomolecules compared to ionic surfactants. Surfactants with two or more hydrophobic tail groups of different lengths frequently form w/o-MEs more readily than one-tailed surfactants without the requirement of cosurfactant, perhaps because of their wedge-shaped molecular structure [17,41]. 

Steinbrech, B., Neugebauer, D., Zulauf, G. (1986). Determination of surfactants by liquid chromatography (HPLC). Reversed phase ion-pair chromatography of alkyl sulfates and alkyl sulfosuccinates. Analytische Chemie 324(2), 154—157. 

The solubility of water is extremely low in hydrocarbons. For example, as low as 0.7% of water form the separate phase in decane (T = 298 K) [22], The surfactants create a small water micelle in hydrocarbon. For example, sodium bis-2-ethylhexyl sulfosuccinate (AOT) in the ratio H2O AOT = 20 creates stable micelles in decane with the diameter room temperature) [22]. The radii of a micelle r depends on the ratio H20 A0T the dependence has the following form [29] ... 

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